Such an injection-molding nozzle is known from DE 195 42 237 [U.S. Pat. No. 5,507,634], which is provided as a hot-runner nozzle having an integrated electric heating element, and having a central borehole as a flow passage for conveying the thermoplastic melt to the nozzle tip and then into the cavity of a cooled mold or a separable mold block having the mold cavity provided in a mold plate. The mold plate may form multiple mold cavities, and the injection mold may be correspondingly provided with multiple injection-molding nozzles.
The hot-runner nozzle comprises an elongated central body seated in a one-piece outer collar or a flange housing provided with a flange part as housing collar. The central body comprises, on its elongated central shaft part on its rear end, another flange or housing collar that is shaped like a cloverleaf and engages positively into the correspondingly contoured housing collar or flange of the outer collar or of the flange housing. The injection nozzle constructed in this manner by insertion into each other is placed with the rear flange or housing collar into a seat in a plate on the hot tool side and screwed down.
Another embodiment of such a hot-runner nozzle known from EP 0 528 315 [U.S. Pat. No. 5,312,241] consists of a rather broad flange body provided with lateral electrical connections that is extended as a narrow shaft through which a material tube heated from the outside extends. This shaft has several parts including an outer casing tube with an upper collar for contacting upon insertion into a mold-cavity plate. The material tube with the flow passage emptying into nozzle tips is designed on its rear end with a shoulder-like outer collar via which the material tube is connected to the flange body or tubular flange housing by welding where it contacts front surfaces lying on each other. A cap placed over the extending shoulder piece of the jacket tube forms the rear closure of this hot-runner nozzle.
In a hot runner-or cold runner nozzle used in injection-molding tools and known from DE 100 04 072 [U.S. Pat. No. 6,805,549], in order to supply a fluent mass at a preset temperature under high pressure to a separable tool block (mold cavity), the nozzle body comprises at least one substantially planar level lateral surface to which an surface heating and/or cooling apparatus is attached.